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Tina Muir is Developing Resources to Understand and Combat RED-S

The former elite marathoner is intent on helping other athletes avoid RED-S, the condition that foiled her elite running career

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For the last several years, Tina Muir has been an outspoken advocate for athletes navigating the challenges of RED-S. The condition, known as relative energy deficiency in sport, occurs when athletes don’t get enough fuel through food to support the energy demands of training. It can be detrimental to reproductive health, bone health, and immunity, among other systems throughout the body.

The St. Louis-based Muir, a podcast host, author, former elite marathoner, and mom of two, has written articles and spoken on panels about her own experience with RED-S while competing as a professional runner. Now she’s taking her efforts a step further by offering a new, comprehensive platform aimed to provide athletes with the tools to support their own health and wellbeing.

In February, Muir, 34, created RED-S: Realize. Reflect. Recover, a subscription-based community resource that shares educational videos, guides, and access to one-on-one conversations with experts in the field. In total, she has published 129 videos on her YouTube channel, Running for Real, that share insights from medical, nutrition, and sports performance specialists.

Creating the platform was a massive undertaking, but one that felt critical to Muir, who wants to help other athletes avoid the same pitfalls and heal from the condition that led to an early retirement for the runner.

Tina Muir
Tina Muir retired from elite running at the age of 28 (Photo: Sandy Gutierrez)

Muir grew up in St. Albans, England, and moved to the U.S. to run on the track and cross-country team at Ferris State University in Big Rapids, Michigan. While competing for the Division II school, she earned 11 All-American honors and finished third in the 10,000 meters at the 2012 British Olympic Trials. After she graduated, Muir ran professionally for several years, eventually earning personal bests of 1:13 in the half marathon and 2:36 in the marathon.

While Muir’s results showed success on paper, she struggled internally.  “I felt so broken and so alone during those nine years of my collegiate and professional career,” she told Women’s Running.

For nearly a decade, Muir didn’t get her period, one of the symptoms of RED-S. At the time, doctors told her the cause of her amenorrhea, or lack of menstruation, was because of her running and if she wanted to get her period back, she’d need to quit. Although she was rarely injured, Muir also dealt with other symptoms of RED-S, including brutal insomnia.

“I felt tired all the time, and yet I couldn’t sleep, and a lot of that was because of the high level of stress that I put myself under trying to be a perfectionist,” she said.

Retirement at 28

At the peak of her pro career, Muir competed at the 2016 IAAF World Half Marathon Championships. But in the months after meeting her long-term goal, Muir reached one of her lowest points. On top of her physical health, her mental health was also declining. “I was concerned with the way I looked and even to the detriment of my performance at that point,” she said. “I wanted to look fast over making sure I was as fast as I could be.”

When her sister had a baby, Muir’s perspective began to shift. Witnessing the joys of motherhood made her realize what she was risking by not having a regular period. And she wanted to start a family.

In 2017, Muir shocked the running world when she announced her retirement at the age of 28.

“When I stopped running, I realized my heart wasn’t in the sport anymore. And I realized that I could finally step away, and do something about it, be brave, and tell others in my situation that they were not alone,” she wrote at the time.

In the same year, Muir launched her podcast, Running for Real, a series of conversations that center on encouraging runners of all abilities. Over the years, she’s interviewed notable guests, including Malcom Gladwell, Ryan Holiday, Des Linden, and Reshma Saujani.

In conversations with dietitians and psychologists, Muir gathered informative snippets that touched on RED-S, but she wanted to create a more digestible, expansive resource to educate high school and college athletes about the condition. So, she created the platform.

“My primary goal was that if I could get it to spread to high school and collegiate athletes, then maybe we could prevent or encourage the next generation of runners to put fueling their body as the number one factor over looking a certain way,” she said, explaining that while awareness and resources have improved in the last several years, there’s still much to be done, especially among coaches in the collegiate ranks.

“I hope that by giving power to the athletes, and not in an accusatory way towards coaches, but just giving them the knowledge to know what is and what isn’t okay for their bodies, they can then make choices for themselves that put their health first,” she said.

In partnership with sports psychologist Dr. Marissa Norman, eating disorder specialists Dr. Jennifer Gaudiani and Amanda Tierney, and sports nutrition experts Rebecca McConville and Nancy Clark, Muir produced short video clips that answer common questions, address key findings, and touch on the physical and psychological effects of RED-S, among other topics related to the condition.

These days, Muir runs for many different reasons—exploration, mental health, to offer support as a guide, and at times, to meet a challenging goal. Over the years, she’s discovered that running doesn’t need to be solely for achievement. It can be whatever she needs it to be each day.

To her surprise, working on the series also proved to be healing for her. Now she hopes the platform can provide the same effect for other runners.

“The eating restriction that I did, not getting enough calories in my diet as a runner, I thought I had worked through, but I think [this work] showed me that most of us don’t have the compassion and self-respect for ourselves that we have for others,” she said. “We need to treat ourselves with respect and love in the way that we would with other people.”

RELATED: Tina Muir’s Injury Prevention Tips for New Runner Moms

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